1. As I already implied, I almost always modify the problems to get
more mileage out of them. With experience, I notice that it's often
necessary to more fully "close the loop" on some problems, asking
students to plot results, substitute trial numerical values, examine
interesting limiting cases, etc. The "solutions manual" don't have
all this. I can also ask for explanations of intermediate steps or
alternative methods to get them. (Also there's the phenomenon of new
editions of texts. That doesn't work so well for Griffiths, but does
happen more with mechanics texts in my experience.)
2. Mike Monce complained this takes a lot of time. Absolutely true.
Teaching a new course is therefore a *major* undertaking for me.
Fortunately I love it and don't mind sacrificing a night a week of
sleep for it. I know fully well a new course will take me at least 5
hours of prep for every classroom hour. But it gets easier with
subsequent passes through the course. Usually the first time I just
try to survive and learn as much as I can about the physics and
generally go ask the previous instructor to give me copies of their
homework and tests to "crib off" at least in part. (Even better, I
try to sit in on their course if I know I'll be teaching it next. So
far I have sat through at least 5 courses--in their entirety--taught
by colleagues, including doing all the homework.)
--
Carl E Mungan, Assoc Prof of Physics 410-293-6680 (O) -3729 (F)
Naval Academy Stop 9c, 572C Holloway Rd, Annapolis MD 21402-5002 mailto:mungan@usna.eduhttp://usna.edu/Users/physics/mungan/